diff --git a/calculator/calculator.app.js b/calculator/calculator.app.js
index 693f53a..e95adb9 100644
--- a/calculator/calculator.app.js
+++ b/calculator/calculator.app.js
@@ -54,7 +54,7 @@ var operators = {
 if (process.env.HWVERSION!=1) {
   operatorsGrid = [2, 4];
   operators['='].grid = [1, 3];
-  operators.r = {grid: [0, 2], val: '√'};
+  operators.r = {grid: [0, 2], val: 'sqrt'};
   operators.s = {grid: [1, 2], val: 'x^2'};
 }